Multi-piece conveyor component including hygienic connection

ABSTRACT

A multi-piece component for a conveyor comprises a first section and a second section that mates with the first section around a shaft using a hygienic fastener to form a complete module. The hygienic fastener seals an interface between the fastener and the first section and between the first section and the second section. Chamfers facilitate positioning of the multi-piece component on a shaft.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 62/876,344, filed Jul. 19, 2019, the contents of which areherein incorporated by reference.

BACKGROUND

The invention relates generally to conveyor drives and components thatcan be assembled on a shaft in an endless conveyor belt system.

Drives, such as sprockets and pulleys, are used to drive or otherwiseengage endless power-transmission and conveyor belts and chains. Drivesmounted on a drive shaft are received by a bore extending axiallythrough the drive. A motor drives the drive shaft to impart motion tothe drive. Installing a one-piece drive on a drive shaft requires thatat least one bearing block on an end of the drive shaft be removed toslide the drive axially onto the shaft. Typically, the drive shaft alsohas to be lifted out of the conveyor side frame.

Scrolls are idle devices mounted on a shaft in a conveyor that contactthe inside of a conveyor belt to move debris away from the center of theconveyor belt.

Split drives that are split along seams through their bores can beinstalled on drive shafts without removing bearing blocks. A first pieceof the split drives is positioned on the drive shaft. Then, acomplementary second piece is mated to the first piece. The two piecesare fastened to each other. Split drives and other split components maypresent hygiene issues and issues with properly positioning the drive onthe drive shaft.

SUMMARY

One version of a shaft-mounted conveyor component embodying features ofthe invention comprises first and second components that mate to form amodule using a hygienic connector. Recesses on the shaft may facilitatepositioning of the split shaft- mounted component in a proper position.

According to one aspect, a multi-piece component for a conveyor beltcomprises a first section comprising a hub for engaging a first portionof a shaft, a peripheral surface for engaging a conveyor belt and aconnecting protrusion including first opening for a fastener.

A second section is coupled to the first section and comprises a hub forengaging a second portion of a shaft and a second opening for thefastener configured to align with the first opening in the firstsection. A fastener is inserted through the first and second opening tofasten the first section to the second section. A first sealing elementseals the interfaces between the fastener and the first section. Asecond sealing element seals the interfaces between the first sectionand the second section.

According to another aspect, a conveyor includes a laterally-extendingshaft with a first corner chamfer and a multi-piece component mounted onthe shaft. The multi-piece component includes a first section with a hubhaving an angled interior surface configured to engage the first cornerchamfer, a peripheral surface for engaging a conveyor belt and a firstopening for a fastener. A second section is coupled to the first sectionand comprises a hub for engaging the shaft opposite the first second anda second opening for the fastener configured to align with the firstopening. A fastener is inserted through the first and second opening tofasten the first section to the second section. Sealing elements seal aninterface between the fastener and the first section, and an interfacebetween the first section and the second section.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a shaft-mounted conveyor componentcomprising a plurality of helical modules arranged in series on a shaftto form a helical pulley;

FIG. 2 is an isometric view of a helical module of the conveyorcomponent of FIG. 1 according to an embodiment of the invention;

FIG. 3 is an isometric view of the two portions of the helical module ofFIG. 2;

FIG. 4 is an exploded view of the helical module of FIG. 2;

FIG. 5 is a front view of the helical module of FIG. 2;

FIG. 6 is an isometric view of the helical module of FIG. 2 duringassembly on a shaft;

FIG. 7 is an isometric view of a shaft with chamfers suitable forreceiving the helical module of FIG. 2;

FIG. 8 is a front view of the helical conveyor pulley of FIG. 1;

FIG. 9 is an isometric view of a conveyor drive comprising multiplemating components arranged in series according to another embodiment;

FIG. 10 is a front view of a sprocket of the conveyor drive of FIG. 9;

FIG. 11 is an isometric view of the sprocket of FIG. 10;

FIG. 12 is a reverse view of the sprocket of FIG. 10;

FIG. 13 is a semi-exploded view of the sprocket of FIG. 10;

FIG. 14 is an exploded view of the sprocket of FIG. 10;

FIG. 15 shows a first mating component of the sprocket of FIG. 10 duringassembly on a driveshaft;

FIG. 16 is an isometric bottom view of the first mating component ofFIG. 15, detailing uneven chamfers;

FIG. 17 shows a shaft with uneven chamfers suitable for receiving thefirst mating component of FIG. 16;

FIG. 18 shows a shaft with a continuous chamfer suitable for mounting aseries of stacked sprockets;

FIG. 19 shows a conveyor component comprising a half disk;

FIG. 20 is a partially exploded isometric view of another version of ahelical module as in FIG. 2 with a clamp portion having retainedfastening hardware;

FIG. 21 is an axial view another version of a shaft-mounted conveyorcomponent embodying features of the invention.

DETAILED DESCRIPTION

A shaft-mounted conveyor component for driving, cleaning, guiding orotherwise engaging a conveyor belt comprises multiple portions that matetogether about a rotatable shaft with a hygienic connection. Theinvention will be described below relative to certain illustrativeembodiments, though the invention is not limited to the illustrativeembodiments.

One version of a split shaft-mounted component embodying features of theinvention is shown in FIG. 1. The illustrative shaft-mounted conveyorcomponent 10 is a helical pulley formed by a plurality of modules joinedtogether. Each half-turn of the helix is formed by a pair of matingcomponents forming a module 100. A series of modules 100 is arranged ona shaft 12, with the ends of each half-turn adjacent to each other toform the helix. The outer surface 14 of the helix forms a peripheralsurface for contacting a conveyor belt to move debris away from theconveyor belt. The illustrative conveyor shaft 12 has a square-shapedcross-section, but the invention is not so limited.

Referring to FIGS. 2 and 3, each module 100 comprises a scroll portion110 forming a half-coil of the helix and a clamp portion 150 for matingwith the scroll portion to affix the scroll portion to a shaft. Thescroll portion 110 comprises a hub 120 for interfacing with the shaftand a web 112 extending from a first edge 113 to a second edge 114 in ahelical manner. The illustrative web 112 has a consistent thickness,terminating in outer surface 14. The first edge 113 of the web alignswith a first end 121 of the hub 120 and the second edge 114 aligns witha second end 122 of the hub 120, with the web 112 arcing and twisting toform a half-coil, but the invention is not so limited. In theillustrative embodiment, the first edge 113 and second edge 114 arestraight and substantially perpendicular to the axis of the shaft 12,but the invention is not so limited. The hub 120 further includesthreaded openings 124, which may be inserts and may have a closedbottom, at each side for receiving fasteners to fasten the clamp portion150 to the scroll portion 110. The web orientation may be reversed toform a helix having an opposite coil pattern.

The clamp portion 150 includes a hub forming a bridge 152 between twochannels 154 configured to align with the openings 124. Fasteners 170inserted through the channels 154 and aligned openings 124 secure theclamp portion 150 to the scroll portion 110. In one embodiment, thefasteners 170 are bolts, received and anchored in the threaded openings124. The bridge 152 receives the opposite side of the shaft from theportion received in the hub of the associated scroll portion.

Referring to FIG. 4, the module 100 further includes sealing elements,such as sealing washers 180, for sealing the interfaces between theclamp portion 150 and scroll portion 110 and between the clamp portion150 and the heads of the bolts 170. The sealing washers 180 eliminatesandwiches to enhance hygiene. In one embodiment, a sealing washer 180may comprises a metal flat ring seal with an elastomer rim. For example,the metal ring may have a plastic or elastomeric material, such as PTFE(polytetrafluoroethylene), EPDM (ethylene propylene diene monomer)rubber or EDT (ethylene propylene diene terpolymer), or others known inthe art, bonded to the ring's outer diameter. One commercially availablesealing washer is the “Hygienic Usit Ring®” available from FreudenbergSealing Technologies of Weinheim Germany. Alternatively, a sealingelement may be integrated into the fastener with a plastic material,such as Polytetrafluoroethylene (PTFE) or ethylene propylene dienemonomer (EPDM), bonded to the outside diameter of the face 169 of thebolt head. Or the sealing elements may be integrated into the scrollportion and the clamp portion 150 with a process such as overmolding or2-shot liquid silicon rubber molding.

As shown in FIG. 5, when the scroll portion 110 and clamp portion 150are connected together using the fasteners 170, the hub 120 and bridge152 form an opening 190 for the shaft. The illustrative opening includescleaning recesses 191. The bridge 152 includes rounded reliefs 192 forthe corners of the shaft. The hub 120 includes protrusions 193 in theform of filling structure in the hub 120 that fills in the two cornersof the opening 190. In this version the protrusions are angled surfacesor chamfers 194 at the corners that interface with chamfers on the shaftto provide axial retention of the module on a shaft. Other suitablemeans for securing the axial position of the component relative to theshaft may be used. As also shown in FIG. 5, the bolt 170 is received inand retained by the threaded openings 124 in the hub 120 and the sealingwashers 180 sealing the interfaces between the scroll portion 110 andthe clamp portion 150 and between the bolts 170 and the clamp portion150.

Referring to FIGS. 6 and 7, a shaft 12 for receiving the modules 100 toform a helical pulley includes selected recesses, in the form of shaftchamfers 198 in selected corners of the shaft in this example, forinterfacing with the angled surfaces 194 on the hub 120 to limit theaxial movement of the modules 100 and to properly position thecomponents on the shaft. The shaft has a square cross-section, but theshaft can have a cross-section in the shaft of another quadrilateral oranother suitable shape. Alternatively, the shaft 12 may have recesses ofother shapes and formed at other positions on the periphery of theshaft, and the one or more components 110, 150 may include complementaryprotrusions other than chamfers to facilitate assembly and restrictmovement of the components. As shown, the shaft chamfers 198 are offsetfrom each other to fit the corresponding angled surfaces 194 on thehelix hub 120.

The clamp portions 150 are fastened to the scroll portions 110 aroundthe shaft 12 at the positions of the shaft chamfers 198. The modules 100may be clamped tightly to the shaft 12. But for better cleanability themodules enclose the shaft 12 with limited clearance to allow cleaningbetween the shaft and contact faces 199 bounding the opening 190 thecleaning recesses 191 and the rounded reliefs 192 and the angledsurfaces 194. The limited clearance is great enough to allow cleaningbetween the shaft 12 and half the contact faces 199 during any part ofthe shaft's rotation. And the clearance is small enough to prevent themodules 100 from sliding axially out of their positions at the shaftchamfers.

Other suitable means for axially retaining the module 100 relative tothe shaft 12 may be used, and the invention is not limited to theillustrative chamfers. For example, the hub 120 and—or bridge 152 mayinclude a protrusion, tab, slot, recess or other feature configured toengage with a corresponding recess, slot, protrusion, tab or otherfeature on the shaft.

Referring to FIG. 8, when multiple modules 100 a, 100 b are assembled ona shaft 12 to form a helix, the web edges 113, 114 have spaces 18therebetween to facilitate cleaning.

FIGS. 9-10 show another embodiment of a shaft-mounted conveyor component20 comprising multiple components fastened together using bolts asfasteners and sealing washers as sealing elements. But the sealingelements may be integrated into the fasteners or into the individualcomponents forming the conveyor component 20. The conveyor component isa conveyor drive 20 that comprises a series of split sprockets 200mounted to a drive shaft 212, shown as a square shaft, though theinvention is not so limited. The peripheral surfaces of the sprockets200 include teeth 214 or other features for driving a conveyor belt.Each sprocket 200 is formed by a pair of mating components 210, 250assembled together around the shaft 212 and coupled together usingfasteners 270. The illustrative sprocket includes gaps 208 between thecomponents and cleaning windows 291 to facilitate cleaning and promotehygiene.

Referring to FIGS. 11-14, a first mating component 210 comprises a hub220 for engaging a portion of the shaft 212. The hub connects to anouter rim 213 that forms the drive teeth 214 by a central spoke 215 andlateral spokes 216 at the ends of the hub. Shaped connecting tabs 224extend from the lateral spokes 216 and include channels for receivingthe fasteners, shown as bolts 270.

The second mating component 250 comprises a hub 252 for engaging anopposite portion of the shaft from the first hub 220. The hub 252connects to an outer rim 253 with drive teeth 214 via a central spoke255 and lateral spokes 256. Connecting tabs 254 extend from the lateralspokes and include threaded openings, which may be inserts, and may be aclosed bottom, for capturing the bolts 270 to secure the two componentsto each other and on a shaft. In an embodiment, the bolts 270 arerecessed related to the spokes 216, 256 and the rest of the matingcomponents 210, 250 (i.e., not protruding past the thickness of thesprocket) when the sprocket 200 is assembled to allow close, evenstacked, spacing of several sprockets 200 on a shaft. In an embodiment,the threaded openings 254 may be initially offset from the channels 224and pushed into alignment to control orientation of the matingcomponents.

As shown in FIG. 14, sealing washers 280 seal the interfaces between thefirst component 210 and second component 250 and between the firstcomponent 210 and the head of the fastening bolt 270.

In another embodiment of the invention, a mating component 210 or 250may include one connecting tab having a through channel and anotherconnecting tab having a threaded opening, which may be closed and maycomprise a threaded insert, with the connecting tabs offset so as tomate with a corresponding mating component also having each type ofopening.

Referring to FIGS. 15 and 16, a mating component for a drive, shown asthe mating component 250, may include chamfers in a hub 252 forinterfacing with chamfers 298, 299 on an associated shaft 212. Thechamfers ensure proper orientation and prevent migration of the drivealong the drive shaft. As shown in FIG. 16, a first hub chamfer 294 maybe wider than a second hub chamfer 295, caused by reducing the thicknessof the hub 252′ around the second hub chamfer 295 in a mating component250. The associated shaft 212, shown in FIG. 17, may have first chamfers298 at a first edge that are wider than second chamfers 299 at a secondedge to mate with the chamfers 294, 295, respectively, thus ensuringproper orientation of the assembled drive 200 on the shaft 212. Like thescroll modules 100 of FIG. 6, the two mating components 210, 250 do notnecessarily have to be tightly clamped to the shaft 212. Rather, theymay be fastened together so as to merely enclose the shaft 212 with alimited clearance—enough to allow cleaning of the contact surfaces onthe hubs 220, 252 bounding the shaft opening as the shaft completes onerotation.

As shown in FIG. 18, a drive shaft 312 may include a continuous chamfer398 on a first edge with selectively spaced chamfers 399 on an oppositeedge for accommodating a series of stacked sprockets 200 on the shaft.

FIG. 19 shows one half of a shaft-mounted component similar to the splitsprocket of FIG. 16. A half disk 400 is used with a complementary halfdisk to form a shaft-mounted disk used to support a conveyor belt andserve, for example, with other such multi-part disks mounted on theshaft as part of a return roller system in a conveyor-belt return run.The half disk 400 differs from the halves of the split sprocket in thein that its rim is smooth—devoid of teeth or other belt engagementstructure.

In FIG. 20, the fasteners are held captive to the clamp portion 150. Areduced shank bolt or screw 470 has a threaded end 472. The outerdiameter of the threads 472 is greater than the diameter of the bolt'sshank 474. After the bolt 470 with the outer sealing washer 180 isinserted through the channel 154, a sealing washer 480 having a threadedinner bore is threaded onto and past the threaded end 472 so that itsits on the reduced diameter shank 474. The internally threaded sealingwasher 480 is captured on the bolt 470, and the bolt is captured by thethreaded sealing washer in the bore of the clamp portion 150. So, whenthe clamp portion is unfastened from the scroll portion 110, the bolts470, the washers 180, 480, and the clamp portion 150 remain together.They are separated only by intentionally unscrewing the internallythreaded sealing washers 480 from the reduced shank bolt 470. The samecaptured fasteners can be used with other multi-part shaft-mountedcomponents, including the split sprocket and the split disk.

Another version of the scroll module is shown on FIG. 21. The scrollportion 510 and the clamp portion 550 are split along a diagonal of asquare central opening 590 for a rectangular shaft 512. The penetrationdepth of contact faces 599 from the hubs into the opening 590 is deepenough for the clamp portion and the scroll portion to be clampedtogether on the shaft 512 and against the sealing washers 580.

Although the invention has been described with reference to a fewversions, other versions are possible. The scope of the invention is notmeant to be limited to the details of the various exemplary versions.

What is claimed is:
 1. A multi-piece component for a conveyor beltcomprising: a first section comprising a hub for engaging a firstportion of a shaft, a peripheral surface for engaging a conveyor beltand a connecting protrusion including first opening for a fastener; asecond section coupled to the first section comprising a hub forengaging a second portion of a shaft, the second section including asecond opening for the fastener configured to align with the firstopening in the first section; and a fastener inserted through the firstand second opening to fasten the first section to the second section;and a first sealing element that seals the interfaces between thefastener and the first section, and a second sealing element that sealsthe interfaces between the first section and the second section.
 2. Themulti-piece component of claim 1, wherein the first and second sealingelements are metal washers with a plastic bonded to the metal washers'outside diameter.
 3. The multi-piece component of claim 2, wherein theplastic comprises polytetrafluoroethylene or ethylene propylene dienemonomer.
 4. The multi-piece component of claim 1, wherein the firstsection includes a helical web.
 5. The multi-piece component of claim 1,wherein the first section includes a circular half disk.
 6. Themulti-piece component of claim 1, wherein the first and second sectionsinclude an outer rim comprising drive teeth for engaging a conveyorbelt.
 7. The multi-piece component of claim 1, wherein the hub of thefirst section includes a protrusion for engaging with a recess on theshaft.
 8. The multi-piece component of claim 1, wherein the recess is afirst chamfer and the protrusion is a complementary second chamfer. 9.The multi-piece component of claim 8, wherein the hub of the firstsection includes a third chamfer that is thinner than the second chamferfor engaging a fourth chamfer on the shaft.
 10. The multi-piececomponent of claim 1, wherein the fastener includes a reduced shank boltwith a threaded end and a reduced diameter shank and wherein the secondsealing element is a sealing washer that is internally threaded and isscrewed along the threaded end and onto the shank to be retained on theshank unless intentionally unscrewed from the bolt.
 11. The multi-piececomponent of claim 1, wherein the first and second openings form anopening to receive a square shaft enclosed by the first and secondsections fastened together.
 12. The multi-piece component of claim 11,wherein the first and second sections are split along a diagonal of theopening.
 13. The multi-piece component of claim 11, wherein the firstand second sections are split along a side of the opening.
 14. Themulti-piece component of claim 1, wherein the first and second sealingelements are integrated into the first section with a process.
 15. Themulti-piece component of claim 1, wherein the fastener is a bolt havinga bolt face and wherein the first sealing element is integrated into thefastener with a plastic material bonded to the outside diameter of thebolt face.
 16. In a conveyor for moving items longitudinally from afirst end to a second end, a laterally-extending shaft with a firstcorner chamfer; and a multi-piece component mounted on the shaft,comprising: a first section including a hub with an angled interiorsurface configured to engage the first corner chamfer, a peripheralsurface for engaging a conveyor belt and a first opening for a fastener;a second section coupled to the first section comprising a hub forengaging the shaft opposite the first second, the second sectionincluding a second opening for the fastener configured to align with thefirst opening; a fastener inserted through the first and second openingto fasten the first section to the second section; and sealing elementsfor sealing an interface between the fastener and the first section, andan interface between the first section and the second section.
 17. Theconveyor of claim 16, further comprising a second corner chamfer on theshaft that is thinner than the first corner chamfer.
 18. The conveyor ofclaim 17, wherein the hub of the first section includes a second angledinterior surface that is thinner than the first angled interior surfacefor engaging a the second corner chamfer on the shaft.
 19. The conveyorof claim 16, wherein the sealing elements are metal washers with aplastic bonded to the metal washers' outside diameter.